How to override core class which is already overrided by other custom module in Magento 2

Question

How to override core class which is already overrided by other custom module

I have module1 and module2 overriding CatalogSearch module.

in Module1

etc/di

<preference for="Magento\CatalogSearch\Controller\Result\Index" type="Vendor\Module1\Controller\Result\Index" />

in Controller class

class Index extends \Magento\CatalogSearch\Controller\Result\Index
{
 public function __construct(
    Context $context,
    Session $catalogSession,
    StoreManagerInterface $storeManager,
    \Magento\Framework\View\Result\PageFactory $resultPageFactory,
    Resolver $layerResolver,
    QueryFactory $queryFactory


) {
     parent::__construct($context,$catalogSession,$storeManager,$resultPageFactory,$queryFactory,$layerResolver);
     $this->resultPageFactory = $resultPageFactory;
     $this->layerResolver = $layerResolver;
     $this->_queryFactory = $queryFactory;
     $this->_storeManager = $storeManager;
}

In Module2

etc/di

<preference for="Vendor\Module1\Controller\Result\Index" type="Vendor\Module2\Controller\Result\Index" />

In Controller class

 class Index extends \Vendor\Module1\Controller\Result\Index
 {
    public function __construct(
    Context $context,
    Session $catalogSession,
    StoreManagerInterface $storeManager,
    Http $request,
    LayoutInterface $layout,
    ScopeConfigInterface $scopeConfig,
     Resolver $layerResolver,     
    \Magento\Catalog\Model\CategoryFactory $catalogCategoryFactory,
    \Magento\Framework\Registry $registry,
    \Vendor\Module1\Model\Client\Connector $tglssearchClientConnector,
    QueryFactory $queryFactory,
    \Magento\Framework\View\Result\PageFactory $resultPageFactory
) {
    parent::__construct($context,$catalogSession,$storeManager,$queryFactory,$layerResolver);
        $this->_storeManager = $storeManager;
        $this->catalogSession = $catalogSession;
        $this->storeManager = $storeManager;
        $this->request = $request;
        $this->layout = $layout;
        $this->scopeConfig = $scopeConfig;
        $this->catalogCategoryFactory = $catalogCategoryFactory;
        $this->registry = $registry;
        $this->tglssearchClientConnector = $tglssearchClientConnector;
        $this->layerResolver = $layerResolver;
        $this->_queryFactory = $queryFactory;
        $this->resultPageFactory = $resultPageFactory;

    /* parent::__construct(
        $context
    ); */
}

I get below error,

Argument 4 passed to Vendor\Module1\Controller\Result\Index::__construct() must be an instance of Magento\Framework\View\Result\PageFactory, instance of Magento\Search\Model\QueryFactory given, called in C:\xampp\htdocs\magento2x_5test\app\code\Vendor\Module2\Controller\Result\Index.php on line 36 and defined in C:\xampp\htdocs\magento2x_5test\app\code\Vendor\Module1\Controller\Result\Index.php on line 22

Answer 1

Module ONE is overriding some core class, if you want to override same core class already used/override module ONE, override Module ONE class by using your module( Module Two )as below example.

Module ONE as Vendor/Module

Vendor/Module is extending Magento\CatalogSearch\Block\Result

In di.xml

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Magento\CatalogSearch\Block\Result" type="Vendor\Module\Block\Result"/>
</config>

In Block result.php

<?php
/**
 * Copyright © 2016 Magento. All rights reserved.
 * See COPYING.txt for license details.
 */
namespace Vendor\Module\Block;


/**
 * Product search result block
 */
class Result extends \Magento\CatalogSearch\Block\Result
{
   public function getSearchQueryText()
    {

die('Module ONE');
// Some code
return parent::getSearchQueryText();
    }

}

Module TWO as Vendor/Moduletwo

Vendor/Moduletwo is extending Vendor\Module\Block\Result

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Vendor\Module\Block\Result" type="Vendor\Moduletwo\Block\Result"/>
</config>

In block result.php

<?php
/**
 * Copyright © 2016 Magento. All rights reserved.
 * See COPYING.txt for license details.
 */
namespace Vendor\Moduletwo\Block;


/**
 * Product search result block
 */
class Result extends \Vendor\Module\Block\Result
{
   public function getSearchQueryText()
    {

die('TWO');
// Some code
return parent::getSearchQueryText();
    }

}

In this case both extension functionalities will work.

Answer 2

To solve this error, correct the sequence of the arguments in the parent::__construct(arg1, arg2, . . .) method. It must be same as it is in the parent's __construct().

so, to remove this error :

change

parent::__construct($context, $catalogSession, $storeManager, $queryFactory, $layerResolver);

to

parent::__construct($context, $catalogSession, $storeManager, $resultPageFactory, $layerResolver, $queryFactory);

this should solve the mentioned error.